The Denver steak was introduced to the public in 2009, then virtually disappeared until 2012, when it re-emerged in a few food publications, such as Fine Cooking and Saveur, that declared it “new to the market” and “a new classic,” and then it disappeared again. These days, few chefs or diners around the country — let alone residents of the city for which it was named — are aware of the Denver steak, and it’s almost impossible to find the cut at a restaurant that doesn’t butcher its own beef.